Field - and Photoassisted Field Emission Studies of Calcium Fluoride Coated Silicon Tips V.N. Konopsky, V.V. Zhirnov, N.S. Sokolov, J.C. Alvarez, E.I. Givargizov, L.V. Bormatova, V.S. Letokhov et S.K. Sekatskii J. Phys. IV France, 06 C5 (1996) C5-129-C5-134 DOI: 10.1051/jp4:1996521